const path = require('path');

let pathstr = 'a/b/c/d/index.html';

console.log(path.parse(pathstr));
console.log(path.extname(pathstr));
console.log(path.basename(pathstr));


console.log(path.join(__dirname,'..','01.自定义模块','js/a.js')); //'D:\Users\Desktop\48班(0914期)三阶段\代码\day_05\01.自定义模块\js\a.js'